|Sapphire HD4890 Toxic Vapor-X 11150-01-40R|
|Reviews - Featured Reviews: Video Cards|
|Written by Olin Coles|
|Tuesday, 09 June 2009|
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HD4890 Toxic Closer Look
Of the many different product lines Sapphire offers, it's the Toxic design that draws the most attention. Combining best-in-class Vapor-X cooling with factory overclocked settings matched only by the Atomic water-cooled series, the Toxic brand is the most elite air-cooled video card Sapphire offers.
In many regards, the reference HD4890 looks extremely familiar. Sapphire helps differentiate their product by adding a unique cooling solution to an otherwise unchanged video card. The reinvented RV770 GPU found in the Radeon HD 4850/4870 video cards is now calling itself the RV790 and lives in the Radeon HD 4890. If you weren't given more details about the new Radeon 4890, the video card could be mistaken for a polished-up 4870. The Sapphire HD4890 Toxic Vapor-X looks different than the others, but is there really difference?
The Sapphire HD4890 Toxic Vapor-X cannot be denied its roots, because when you compare it against the Radeon HD 4870 the outward differences are negligible. ATI originally designed the Radeon HD 4870 with a balanced blend of value and performance, and the HD4890 rebuffs the performance while keeping an eye on value. The third generation 55nm RV790 chip uses the industry's most energy efficient manufacturing process and adds an additional three-million transistors, which allows ATI's latest and greatest single-chip graphics card to achieve top-level gaming performance while being more energy efficient at idle. Featuring the industries only major implementation of GDDR5 video frame buffer memory, the RV790 graphics processor is allowed to operate under stress without the worry of burning-up video RAM.
All Sapphire graphics cards in the HD 4000 series incorporate the latest ATI Avivo HD Technology for enhanced video display and feature a second generation built in UVD (Unified Video decoder) for the hardware accelerated decoding of Blu-ray and HD DVD content for both VC-1 and H.264 CODEC's, as well as *.mpeg files, considerably reducing CPU loading. The dedicated HDMI adaptor connects through the S-Video port and has 7.1 surround sound support and delivers audio and video output on a single cable for direct connection to an HDMI ready display. Unfortunately, there is no support for the up-and-coming DisplayPort interface on the Radeon HD 48xx series.
The ATI Radeon HD 4800 Series GPUs can all upscale video up to 2560x1600 resolution on capable dual-link monitors, which is almost twice the display resolution of 1080p HDTV displays. This bodes well for all Radeon HD 48xx owners wanting more from Blue-ray movies, but this isn't a centerpiece feature of the Radeon HD 4890 model 11150-01-40R we're reviewing for this article.
While I am a huge fan of externally-exhausting VGA coolers (such as the one used on reference-design Radeon HD 4890 video cards), I wasn't at all pleased with the exposed electronics that were inherent of the stock cooling package. On the other hand, I am also less enthusiastic about internally exhausting coolers which heat internal hardware, even if they do protect the components. This is the case with the Sapphire Toxic. While the components are free from danger, very little heated air exhausts outside the computer case. Without proper cooling fans or case ventilation, this could potentially affect overclocked hardware stability for the Toxic HD4890 and other components during warmer conditions.
The enhanced cooling unit on the Sapphire Toxic Radeon HD 4890 video card is held tight to the RV790 55nm GPU with the use of a four-corner reinforcing bracket and nine screws. With a die size of 282 mm2, the RV790 GPU offers a greater contact footprint with the cooling unit, compared to the 256 mm2 footprint on the RV770 GPU. The double-height cooler does a very good job of cooling the 4890, but there is still a tremendous amount of heat that builds up on backside of the PCB. If you're an overclocker, there isn't much that can be done to help cool the unit from the reverse side of the circuit board, especially since there are no surface-mounted GDDR5 modules on this side of the video card.
The RV790 operates at 850 MHz by default, and ATI offers top-bin GPUs for factory-overclocked models. Sapphire was fortunate enough to procure 960MHz GPUs for their Toxic series of video cards, making this among the fastest video cards produced today. Ironically, the increase in heat output (which is directly relative) is cured by the Vapor-X cooling solution used on the Toxic. At idle, the Sapphire Radeon HD 4890 Toxic video card recorded a lukewarm 50°C, and under load that number raised to 80°C with an ambient room temperature of 20°C. These are the same temperatures we experienced with overclocked Radeon HD 4870's a few months back, so hopefully our HD4890 benchmark tests will reveal how much has really changed.
In our next section, Benchmark Reviews details our methodology for testing video cards. Following this we offer a cadre of benchmarks to show where the Sapphire Radeon HD 4890 Toxic stands against the top-end market of GeForce and Radeon graphics products... so please read on!